中石油数字化网络服务器虚拟化技术实践及规划.ppt

* * * * * We discussed in the previous slide that a datastore serves up storage space for virtual disks which stores the virtual machine content. As shown in the graphic, a virtual machine is stored as a set of files in its own directory in the datastore. The datastore is formatted as either a virtual machine file system (VMFS), raw data mapping (RDM), or network file system (NFS) volume, depending on the type of physical storage in the datacenter. The datastore can be manipulated (copied, moved, backed-up, and so on) just like a file. New virtual disks can be hot-added to a virtual machine without powering it down. In the subsequent screens we will discuss the datastore types in more depth. ESX lets you have up to 256 VMFS datastores per system with the minimum volume size 1.2GB. By default you can have up to 8 NFS datastores per system and Datastores can also be used for storing ISO images, virtual machine templates, and floppy images. * Now that you understand how storage is presented to the virtual machines and the basic storage terminology. Let’s look at what files make a virtual machine. When you create a virtual machine, ESX automatically creates certain files that are associated with the new virtual machine. Let’s briefly discuss some of the files that compose the virtual machine content folder and what they do: .vmx is the virtual machine configuration. This is the primary configuration file, which stores settings chosen in the New Virtual Machine Wizard or virtual machine settings editor. .vmdk is an ASCII format, which stores the contents of the virtual machines hard disk drive. There could be one or more virtual disk files. -flat.vmdk is single preallocated disk file that contains the data. .vswp are the swap files and are on a per-virtual-machine basis. .nvram is a non-volatile RAM that stores virtual machine BIOS information. .vmem is the virtual machine memory mapped to a file. .vmss is the virtual machine suspend state file, which stores the